Electrostatic separation of muscovite mica from feldspathic pegmatites

The paper presents laboratory experiments for concentrating muscovite mica from feldspathic pegmatites in a high-intensity electric field. The experiments have been carried out on a roll-type research electroseparator and a (0.16...0.4) mm sample. Four separation procedures were tested: (1) DC electrostatic separation with thermal conditioning of the sample; (2) AC electrostatic separation at ambient temperature; (3) DC corona separation using a metallic-surface rotating electrode; and (4) DC corona separation using a dielectric-surface rotating roll. The best quality of mica has been obtained in the last procedure by a three stages separation experiment: 46.11% SiO/sub 2/, 33.64% Al/sub 2/O/sub 3/ and 11.1% (K/sub 2/O+Na/sub 2/O). In all four procedures, the grade of mica concentrate fulfils the requirements of several industrial applications such as welding wires manufacturing.